Human hair contains a thin protective fatty layer of an ante-iso fatty acid, 18-methyl eicosanoic acid (18-MEA), covalently bound to the cuticle. Chemical or mechanical damage to the hair removes portions of this fatty layer making the hair less manageable, less healthy looking and more susceptible to environmental stresses. In the treatment of hair, it is desirable to replenish these ante-iso fatty acids, particularly 18-MEA.
18-MEA is relatively rare in nature and is found in small amounts in materials such as lanolin. Lanolin contains a mixture of fatty acids, including amongst other things, ante-iso fatty acids, as well as hydroxy fatty acids, iso-hydroxy fatty acids, iso fatty acids and unsubstituted fatty acids. U.S. Pat. No. 4,069,347, issuing to McCarthy et al., discloses compositions of quat derivatives of fatty acids derived from lanolin. These lanolin-derived quats are described as being useful, when combined with specific branched-diols, in the preparation of clear cosmetic formulations. These include shampoos and clear hair rinse formulations.